JP3205320B2 - Resin sealing method and resin sealing device for semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin sealing method and a resin sealing device for a semiconductor device.

[0002]

2. Description of the Related Art A semiconductor device on which a semiconductor chip is mounted by a flip chip method has a substrate 10 as shown in FIG.
After the semiconductor chip 12 is flip-chip connected to the semiconductor chip 12, the sealing resin 14
And the resin is sealed at the joining portion. The sealing resin 14 has a function of protecting a joint between the semiconductor chip 12 and the substrate 10 and a function of alleviating a thermal stress caused by a difference in the thermal expansion coefficient between the substrate 10 and the semiconductor chip 12.

[0003] As a method of filling the sealing resin 14 into the joint between the substrate 10 and the semiconductor chip 12, the substrate 10 is tilted and supported as shown in FIG. Generally, a method of pouring the sealing resin 14 into the resin is used. Since a large number of bumps 16 are arranged at the joint portion between the substrate 10 and the semiconductor chip 12, the substrate 10 is tilted and sealed in order to fill the space between these bumps 16 and fill the sealing resin 14. By pouring the sealing resin 14, the sealing resin 14 is filled while pushing out the air in the joint.

[0004]

However, when the joint of the semiconductor chips connected by flip chip bonding is sealed, according to the method of simply pouring the sealing resin 14 as described above, the connection between the semiconductor chip 12 and the substrate 10 is prevented. There is a problem that the joint portion is not completely filled with the sealing resin 14 and air bubbles remain inside the gap. In fact, the gap at the junction between the semiconductor chip 12 and the substrate 10 is very narrow, from 0.1 mm to 0.02 mm and 0.03 mm recently, and a large number of bumps 16 are arranged in the gap. Since the flowability of the sealing resin 14 is suppressed, and the flowability of the sealing resin 14 containing filler is further deteriorated, it is impossible to reliably seal by simply pouring the sealing resin 14. . Also, in terms of work efficiency, the potting method takes longer time to cure the resin than the transfer method, so that the method of pouring and sealing the sealing resin 14 is not effective.

When a flip-chip connected semiconductor chip is to be resin-encapsulated by transfer molding, the height of the bumps and the thickness of the semiconductor chip are slightly different depending on the product to be molded. There is a possibility that the semiconductor chip may be formed in a burred shape or, on the contrary, the semiconductor chip may be broken by strongly pressing the molded article.
Since the gap between the underfill portions is extremely narrow, a resin material containing very small silica or a material containing no silica must be used. Such a resin material easily enters the gap, and if the molded article is not properly clamped, the resin enters the gap and resin burrs are likely to occur. A similar problem occurs even when the plane position of the semiconductor chip with respect to the substrate is slightly shifted. Therefore, it has been almost impossible to seal the underfill portion by flip chip connection with a resin using a conventional transfer molding method.

According to the present invention, in manufacturing a semiconductor device having an underfill structure, such as a semiconductor device in which a semiconductor chip is flip-chip connected, a transfer molding method is applied to assure a reliable underfill without leaving bubbles. It is an object of the present invention to provide a resin sealing method and a resin sealing device for a semiconductor device, which enables a highly reliable semiconductor device to be obtained and enables efficient underfill.

[0007]

The present invention has the following arrangement to achieve the above object. That is, a resin sealing method for a semiconductor device, in which a sealing resin is pressure-fed to an underfill portion of a molded article having a semiconductor chip mounted on a substrate to seal a joint between the semiconductor chip and the substrate, When the molded article is clamped by the mold, the periphery of the underfill portion is closed by a release film except for a portion connected to a gate leading to the underfill portion, and the periphery of the underfill portion is closed by the release film. Then, a sealing resin is pressure-fed to the underfill portion to seal the joint portion. Further, when the underfill portion is closed by the release film, a release film is pressed against a side surface of the semiconductor chip to fill only the inside of the underfill portion with the sealing resin.

When the underfill portion is closed with a release film, the release film is pressed against a side surface of the semiconductor chip via an elastic body which is elastically deformed by a clamping force for clamping a molded product. I do. Further, when closing the underfill portion with the release film, filling the sealing resin into the side sealing portion and the underfill portion provided between the side surface of the semiconductor chip and the release film. It is characterized by. Further, when the underfill portion is filled with the sealing resin, two side surfaces except for one side surface and the other side surface parallel to the one side of the semiconductor chip to which the gate is connected are closed and the resin sealing is performed. It is characterized by stopping. When the underfill portion is filled with the sealing resin, the sealing resin is filled by pulsating the resin.

Further, a molded article having a semiconductor chip mounted on a substrate is clamped by an upper mold and a lower mold, and a sealing resin is pressure-fed and filled into an underfill portion of the molded article to form a seal with the semiconductor chip. A resin sealing device for a semiconductor device for sealing a joint portion with a substrate, wherein one of the upper mold and the lower mold includes:
A cavity is provided for accommodating the semiconductor chip and closing the back and side surfaces of the semiconductor chip via a release film except for an end of a gate which communicates with the underfill portion. Further, an elastic body is provided on a side surface of the cavity concave portion, the elastic body being elastically deformed by a clamping force at the time of clamping a molded article and pressing the release film against a side surface of the semiconductor chip. Further, a pulsating means for pulsating the sealing resin when the sealing resin is pressure-fed to the underfill portion is provided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the resin sealing device according to the present invention will be described below in detail with reference to the accompanying drawings. The resin encapsulation apparatus according to the present embodiment converts a molded product 40 having the semiconductor chip 12 mounted on the substrate 10 by a flip chip method to a bonding portion between the substrate 10 and the semiconductor chip 12 by using a transfer molding method using a release film. The gap portion (underfill portion) is filled with a sealing resin.

The release film can withstand the heating temperature of the mold, and has heat resistance and releasability that can be easily separated from the mold and the resin material, and conforms to the shape of the mold surface provided with the cavity recesses and the like. A method for covering a mold surface with a release film at the time of sealing with a resin and sealing the resin with a resin at the time of resin sealing is called a resin sealing method using a release film. Release films include ETFE, PTFE, PET, FE
P, polyvinylidin chloride, fluorine impregnated glass cloth and the like are used.

According to the transfer molding method using a release film, since the mold surface is covered with the release film, the resin does not come into direct contact with the mold surface at the time of resin sealing, and the molded product is released from the mold. This makes it easy to simplify the configuration of the mold, and it is possible to use the resin most suitable for the product without considering the release of the molded product.

FIG. 1 shows a configuration of a molding die in a resin sealing device for sealing a molded article 40 with a resin, and a resin sealing method. In the figure, the left half of the center line CL shows a state in which the molded article 40 is clamped by the upper die 26 and the lower die 28 via the release film 20, and the right half of the center line CL is the semiconductor chip 12 and the substrate. 10 shows a state in which a sealing resin is filled in a gap portion (underfill portion) of a joint portion 10.

In this mold, one molded article 40 is arranged on each side of the pot 42, and the sealing resin melted in the pot 42 is fed by a plunger 44 to underfill the molded article 40. The portion is filled with a sealing resin. Reference numeral 46 denotes a set recess for setting the molded article 40 at a predetermined position by the lower mold 28. 48 is a mold cull and 50 is a mold runner communicating with the pot 42. 52 is a heater for heating the lower mold 28, and 54 is an air suction hole for supporting the release film 20 set on the lower mold 28 by sucking air on the parting surface of the lower mold 28.

In the upper die 26, a cull insert 60 is provided so as to face the pot 42, and a cavity insert 62 is arranged at a position where the molded product 40 is clamped. The substrate 10 is provided on the parting surface of the cavity insert 62.
A cavity concave portion 62a for accommodating the semiconductor chip 12 mounted on the semiconductor chip 12 is provided via the release film 20 when the molded article 40 is clamped.
Is configured to be closed.

The cavity insert 62 is set in a setting hole provided in the upper die 26 so as to be inserted from the rear side of the upper die 26. A gap serving as an air flow path 64 is provided between the inner wall surface of the setting hole and the side surface of the cavity insert 62. The air flow path 64 is for sucking air from the release film 20 set on the parting surface of the upper mold 26 and sucking and supporting the release film 20 on the parting surface. Reference numeral 66 denotes an air flow path provided on a side surface of the cull insert 60 for sucking the release film 20 by air at a cull portion. Reference numeral 62b denotes a suction hole for suctioning the release film 20 to the inner surface of the cavity concave portion 62a by air.

The parting surface of the upper mold 26 is almost entirely covered with the release film 20, and the inner surface of the cavity concave portion 62 a provided in the cavity insert 62 is also covered with the release film 20. Therefore, the inner surface dimension of the cavity concave portion 62a is set such that the semiconductor chip 12 is accommodated in a state where the cavity concave portion 62a is covered with the release film 20.

Reference numeral 68 denotes an ultrasonic vibrator mounted on the upper die 26. The ultrasonic vibration section 68 is arranged in accordance with the installation position of the gate 70 on the upper mold 26. The ultrasonic vibrating section 68 pulsates the resin passing through the gate 70 to ensure that the underfill portion is filled with the resin. In the case where a resin containing a filler is used as the sealing resin, operating the ultrasonic vibrating section 68 is effective in improving the filling property of the resin. Since the ultrasonic vibrating section 68 is installed via the release film 20, no resin enters the ultrasonic vibrating section 68 and the ultrasonic vibrating section 68
Works stably. In addition, since the inner surface of the resin path portion such as the gate 70 is covered with the release film 20, it is possible to improve the flowability of the resin in the resin path portion at the time of underfill, thereby also improving the resin filling property. Can be done. 74 is the upper base 72
Is a heater provided in the above.

The resin sealing operation by the resin sealing device equipped with the above-mentioned mold is performed as follows. First, the molded article 40 is supplied to the set recess 46 of the lower mold 28 with the mold opened. Next, the release film 20 is supplied to the parting surfaces of the upper die 26 and the lower die 28 by a release film supply mechanism. Release film 20
When supplying the air to the mold, it is slightly separated from the parting surface of the mold, and when it reaches the predetermined position, it approaches the parting surface. Adsorbed to the bearing surface to support.

In this embodiment, the release film 20 to be supplied to the lower mold 28 has a width that covers the pot 42 and the gate end position of the molded article 40 set on both sides thereof. After setting the molded article 40 in the lower mold 28, the lower mold 2
By setting the release film 20 on the opening 8, the opening of the pot 42 is closed by the release film 20, and is covered with the release film 20 to the gate end position on the substrate 10 of the molded article 40.

When the release film 20 covers the portion of the substrate 10 through which the gate 70 passes, the resin passing through the gate 70 does not come into contact with the surface of the substrate 10. The surface of the substrate 10 is not damaged when removing the substrate. If the underfill resin can be adhered to the surface of the substrate 10,
Of course, as described above, the release film 2
It is not necessary to extend 0 and cover it with release film 20. In the case where the sealing resin is adhered to the surface of the substrate 10 to underfill, a portion where the gate 70 passes on the substrate 10 is provided with a good releasability from the sealing resin, for example, a gold-plated portion. Is good.

The release film 20 is divided into a lower mold 28 and an upper mold 2.
After setting on the parting surface of No. 6, a resin tablet 80 for underfill is supplied to the pot 42 of the lower mold 28, and the molded article 40 is clamped by the upper mold 26 and the lower mold 28. When the resin tablet 80 is supplied to the pot 42, the opening of the pot 42 is closed by the release film 20, but the resin tablet 80 is pushed into the pot 42 when the molded article 40 is clamped. Since the release film 20 has sufficient elasticity and flexibility, the resin tablet 80 can be easily pushed into the pot 42. It is more advantageous for the resin tablet 80 to be placed horizontally for the expansion and contraction of the film. Resin tablet 8 supplied to pot 42
After melting, the molten resin is pushed up by the plunger 44, and the molded product 4 is
The sealing resin is filled in the underfill portion of No. 0.

The sealing resin supplied to the pot 42 is not limited to the tablet-shaped resin as described above, but may be a granular, powdery, or liquid resin. It is also possible to use When using granular, powdery or liquid resin,
With the opening surface of the pot 42 covered with the release film 20, air is sucked from the inside of the pot 42, and the release film 2 is moved along the inner surface of the pot 42 and the upper surface of the plunger 44.
0 is absorbed to form a recess for accommodating the sealing resin. If liquid resin is used, plunger 44 and pot 4
The method of using the release film 20 is particularly effective because the resin easily enters between the inner surface of the release film 2 and the inner surface 2.

The wrapping resin is obtained by sealing a predetermined amount of resin with a wrapping film, and includes a resin storage portion formed in a shape that can be stored in the pot 42 and extension pieces extending from the storage portion to both sides. And part. The extended piece is the part where two wrapping films are stacked and sealed,
When the resin pressure is applied, the sealing portion is spread out and passes between the wrapping films to extrude the resin. When the wrapping resin is set in the pot 42, if the edge of the extension piece is located at the gate end position of the molded article 40, the release film 20
The same underfill as in the present embodiment can be performed only by setting the wrapping resin without setting the wrapping resin. Since it is a wrapping resin, it is also possible to use a liquid resin.

FIG. 2 is an enlarged view showing a state where the underfill portion of the molded article 40 is filled with the sealing resin. In the mold runner 50 and the gate 70, the release film 20 is pressed against the inner wall surface of the mold by the resin pressure of the sealing resin 14 fed from the pot 42, and when the sealing resin 14 is filled, the release film 20 The sealing resin 14 does not contact the wall surface. The end of the gate 70 is connected to the semiconductor chip 12 and the substrate 10.
The sealing resin 14 is filled from the gate 70 to the underfill portion, which is connected to the opening end of the gap portion between the sealing resin 14.

The top and side surfaces of the semiconductor chip 12 and the periphery of the joint (underfill) where the semiconductor chip 12 and the substrate 10 are joined are closed by the release film 20 except for the portion connected to the gate 70. From the gate 70 to the underfill portion in the sealing resin 14
Is injected, the underfill portion is filled with the sealing resin 14. As in the present embodiment, the method of clamping the molded article 40 with the mold and applying the resin pressure with the plunger 44 to fill the sealing resin 14 is performed by forcibly filling the underfill portion with the sealing resin. From what you can do,
The underfill portion can be reliably sealed as compared with the conventional method in which the sealing resin is simply poured into the gap.

When the sealing resin is filled by applying a resin pressure by the plunger 44, the application of the resin pressure makes it easier to discharge the air in the underfill portion, and acts to crush the residual air to form a void inside. It is possible to perform highly reliable resin sealing without any problem. Further, even when the gap between the semiconductor chip 12 and the substrate 10 is further narrowed, the resin can be reliably sealed by a method of filling the resin by applying a resin pressure.

According to the method of underfilling using the release film 20, as shown in FIG. 1, since the molded article 40 is clamped via the release film 20, the outer surface of the semiconductor chip 12 is
Semiconductor chip 1 protected by the clamping force
2 can be prevented from being destroyed. Further, by clamping via the release film 20, the sealing property is improved, and it is possible to prevent burrs of the underfill material on the outer surface of the semiconductor chip 12. Further, the substrate 10 on which the semiconductor chip 12 is mounted
Also, by clamping via the release film 20, the sealing property of the underfill portion becomes good,
Burrs of the underfill material on the substrate 10 can be prevented.

As a method of connecting the gate 70 to the underfill portion, a method of connecting the gate to an arbitrary position on one side of the underfill portion to which the gate 70 is connected, or a method of connecting the gate 70 to the underfill portion There is a method in which the sealing resin 14 is filled from the entire side with the entire side to be connected as the gate end. The method of injecting the sealing resin 14 over the entire width of one side has an advantage that the sealing resin can be efficiently injected into the underfill portion.

After the filling of the sealing resin into the underfill portion is completed and the sealing resin is cured, the mold is opened, and the resin-sealed product together with the release film 20 is taken out of the mold. By underfilling via the release film 20, the release of the product is easy, and the release film 20 can be peeled off from the molded product to easily take out only the product. The next underfill operation is performed by setting the molded article 40 on the lower mold 28 with the mold opened and newly setting the release film 20 on the parting surfaces of the upper mold 26 and the lower mold 28. Thus, resin sealing can be performed sequentially by the transfer molding method using the release film.

In the resin sealing device of the above-described embodiment, since the sealing resin is filled by applying resin pressure to the underfill portion of the molded article 40, the parting surface of the cavity insert 62 provided on the upper mold 26 is provided with a cavity. A concave portion 62a is provided;
The periphery of the underfill portion is closed with a release film 20. FIG. 3 shows another embodiment in which the periphery of the underfill portion is closed via the release film 20. In FIG. 3, the left half of the center line CL shows a state before the molded article 40 is clamped, and the right half of the center line CL shows a state where the molded article 40 is clamped.

In the embodiment shown in FIG. 3, the provision of the cavity concave portion 62a for accommodating the semiconductor chip 12 is the same as in the above-described example.
An elastic body 90 such as silicon rubber is provided at a portion where
Is provided. The elastic body 90 is the molded article 4
0, the elastic body 90 is clamped by the clamping force.
Are pressed inward and act to press the release film 20 against the side surface of the semiconductor chip 12 and simultaneously press the release film 20 against the upper surface of the substrate 10.

In FIG. 3, the right half of the center line CL is
7 shows a state in which the periphery of the underfill portion is closed by the release film 20 via the release film 20. When a product having an extremely small gap between the underfill portions is sealed with a resin, it is an important requirement that the underfill portion can be reliably closed. However, the use of the elastic body 90 enables a reliable closing. In addition, an air flow path 92 is provided between the inner side surface of the elastic body 90 and the side surface of the cavity insert 62, and the molded product 40
By applying an air pressure to the elastic body 90 from the air flow path 92 when the is clamped, the pressing force by the elastic body 90 is reinforced and the underfill portion can be closed more reliably.

FIG. 4 shows still another embodiment in which an underfill portion is closed by using an elastic body 90. The left half of the center line CL indicates the mold opening, and the right half of the center line CL indicates the clamping. In this embodiment, the side surface of the cavity concave portion 62a provided in the cavity insert 62 is
And an elastic body 90 such as silicon rubber.
The metal pressing portion 94 acts so that the pressing force concentrates particularly on the side surface portion of the underfill portion when the molded article 40 is clamped, and the elastic body 90 makes the metal pressing portion 94 cover the underfill portion. The action of pressing from the side is reinforced, and the action of pressing the release film 20 against the upper surface of the substrate 10 is performed.

This embodiment also eliminates resin leakage when sealing a product having a very narrow underfill portion with a resin,
In addition, a reliable resin encapsulation is enabled by reliably filling the resin. Also in this case, the release film 20 can be reliably pressed against the side surface of the semiconductor chip 12 by applying the air pressure from the air flow path 92, and the closeability of the underfill portion can be improved.

Other means for closing the periphery of the underfill portion include a method of mechanically moving the block by a driving means such as an air cylinder to close the periphery of the underfill portion, and blowing air from the suction hole 62b. There is a method such as closing with. When the periphery of the underfill portion is closed, all four side surfaces of the semiconductor chip 12 may be closed, or two side surfaces except the side surface connected to the gate 70 and the other side surface parallel to the gate 70 may be closed. And then underfill.

As described above, in the resin sealing method and the resin sealing apparatus according to the present invention, the periphery of the underfill portion of the molded article 40 is closed by the release film 20, and the resin pressure is applied by the transfer molding method. It is characterized by filling with a sealing resin. The method using the transfer molding method enables reliable underfilling by using the above-described ultrasonic vibration. However, it is necessary to control the resin pressure when the sealing resin is extruded by the plunger 44. This also enables reliable resin sealing.

That is, the plunger 44 applies pressure to the resin and pushes the resin to the underfill portion. At this time, the operation of the plunger 44 is discontinuous as shown in FIG. By controlling to extrude, the resin can be extruded in a pulsating manner. The action of filling the resin in such a way as to pulsate the resin is the same as the action by the ultrasonic vibration described above. Even when the sealing resin containing the filler is used, the resin is reliably filled in the underfill portion. Becomes possible.

In the normal transfer molding method, the plunger 44 is continuously pushed up from the lower position to a predetermined height position. However, when the plunger 44 is operated in a pulsed manner, the resin is forcibly pulsed. Therefore, even if there is an obstacle such as the bump 16, the resin is reliably filled, and even if the space between the underfill portions becomes very narrow and the resin is hardly filled, the resin can be reliably sealed. In addition, when the resin is filled by pulsating, the speed at which the resin flows becomes faster, so that when the sealing resin to which the filler is added is used, the filler and the resin are prevented from being separated from each other, and the filler is uniformly filled. Is also distributed, and the distribution of the large-diameter filler and the small-diameter filler can be made uniform.

The flow velocity of the resin in the underfill portion is set to 1
mm / sec, the rising speed of the plunger 44 is 5 μm
Per second. FIG. 5 shows that the plunger 44 is moved upward by about 5 steps in a pulse for about 5 steps per second. Of course, the control content of the plunger 44 can be set as appropriate, and the operation control of the plunger 44 may be controlled in advance in the case of the plunger driving system, for example, in the case of the plunger 44 driven by a servomotor.

The method of controlling the resin filling operation by the plunger 44 as described above may be used in combination with the above-described method using ultrasonic vibration, or may be used in either one. In the case of controlling the plunger 44 to move in a pulsed manner as described above, a normal plunger 44 is used to push the sealing resin 14 from the pot 42 to the gate end. The plunger 44 may be controlled to perform the above-described pulsating operation from the time when the injection of the sealing resin 14 is started.

In the semiconductor device formed by resin sealing using the resin sealing device described above, the sealing resin 14 does not adhere to the side surface of the semiconductor chip 12 as shown in FIG. Only the joining portion is filled with the sealing resin 14. In the semiconductor device, a portion other than the joint portion between the semiconductor chip 12 and the substrate 10 is sealed, since the sealing resin 14 is slightly applied to the side surface of the semiconductor chip 12. (See FIG. 18)
There are various things.

As described above, when the product in which the side surface of the semiconductor chip 12 is sealed with the sealing resin 14 is resin-sealed by using the resin sealing device as in the above-described embodiment, the semiconductor chip 12 is less than the underfill portion. The resin flows first on the side surface of the semiconductor device, and the entire semiconductor device including the underfill portion cannot be properly sealed with the resin. In the following embodiment, a case will be described in which a product in which the side surface portion of the semiconductor chip 12 is also resin-sealed with the sealing resin 14 is resin-sealed.

FIG. 6 is a sectional view showing the configuration of a mold in a resin sealing device for manufacturing the semiconductor device as shown in FIG. The resin sealing device of the present embodiment is a semiconductor chip 1
Steps 62c are formed on the side surfaces of the cavity recesses 62a provided in the cavity insert 62 for sealing the side surfaces of the semiconductor chip 12 with the sealing resin, and the side surface sealing portions 63a, 63b, 63c are formed on each of the four side surfaces of the semiconductor chip 12. , 6
3d is provided.

It should be noted that, as in the present embodiment, the semiconductor chip 1
In the case where the side sealing portions 63a to 63d are provided around the periphery of the second and sealed with resin, a method of simply filling the resin by connecting the gate 70 to the side sealing portion 63a is used.
There is a problem that the resin may be filled first in d and the resin may not be reliably filled in the gap (underfill portion) between the semiconductor chip 12 and the substrate 10.

The distance between the underfill portions is only about 0.1 mm, and the mere connection of the gate 70 to the side sealing portion 63a allows the resin to flow more easily from the side sealing portions 63a to 63d around the semiconductor chip 12. This is because the resin is filled first, and the filling into the underfill portion is the last. Therefore, in order to ensure that the underfill portion is filled with the sealing resin, in the resin molding apparatus of the present embodiment, as shown in FIG. Side blocks 100a and 100b for sealing the two side surfaces are provided and are sealed with resin.

FIG. 7 shows a state where the upper mold 26 is viewed from the parting surface side. A gate 70 is arranged from the pot 42 toward the molded product, and an end of the gate 70 is
Connect to a. Since the side blocks 100a and 100b close the sides of the semiconductor chip 12 over the entire length, the sealing resin 14 fed from the gate 70 is forcibly injected into the gap between the semiconductor chip 12 and the substrate 10.

FIG. 8 shows the arrangement and support structure of the side blocks 100a and 100b in the mold as viewed from the gate 70 direction. In the figure, the left half of the center line CL indicates a state in which the side surface of the semiconductor chip 12 is closed by the side block 100b and the gap between the semiconductor chip 12 and the substrate 10 is filled with the sealing resin 14. The right half of the CL is filled with the semiconductor chip 1 by injecting the sealing resin 14 into the side sealing portion 63c.
2 shows a state in which the side surface of the sealing member 14 is sealed with a sealing resin 14.

The side blocks 100a and 100b are supported by the movable plate 102, and the side blocks 100a and 100b move up and down as the movable plate 102 moves up and down by a driving mechanism such as an air cylinder.
In the resin sealing operation, first, the molded article 40 is set on the lower mold 28, and when the molded article 40 is clamped via the release film 20, the side blocks 100a and 100b on both sides of the semiconductor chip 12 are lowered to underfill. Both sides of the portion are closed, and in this state, a sealing resin is injected from the gate 70.

FIG. 9A shows the side blocks 100a, 10a.
0b shows a state in which the sealing resin 14 is filled with the side surface of the semiconductor chip 12 closed. The sealing resin 14 filling the front side sealing portion 63a passes through the gap between the semiconductor chip 12 and the substrate 10, and the rear side sealing portion 63a.
Fill b. As shown in FIG. 7, by providing the air vent portion 104 on the parting surface of the upper mold 26,
The sealing resin 14 filled in the rear side sealing portion 63b can discharge the residual air in the side sealing portions 63a and 63b and the underfill portion from the air vent portion 104, thereby eliminating the void and underfilling. it can.

When the filling of the resin into the underfill portion is completed, the side block 100 is lowered to the lower position.
a, 100b are lifted, and the side sealing portion 6 is removed from the gate 70.
The sealing resin 14 is injected into 3c and 63d. Fig. 9 (b)
Shows a state in which the sealing resin 14 is filled in the side sealing portions 63c and 63d. Thus, the side block 100
By using the resin sealing device having the components a and 100b, a semiconductor device in which the gap between the semiconductor chip 12 and the substrate 10 and the side surface of the semiconductor chip 12 are resin-sealed with the sealing resin 14 can be obtained.

The above resin sealing device fills the resin when there is a portion where the resin is likely to be filled and a portion where the resin is difficult to be filled depending on the portion of the molded article when filling the cavity or the like with the gate 70. By controlling the flow of the resin at a certain position, accurate resin sealing can be performed as a whole. Such a resin sealing method is an example of a method of securely sealing a resin when there are a portion having good flowability and a portion having poor flowability of a resin in a molded article.

As described above, in the above-described resin sealing apparatus, the sealing resin 14 is filled by applying ultrasonic vibration or pulsating the plunger 44 when filling the sealing resin 14. Pulsation can be applied to 14 to seal it with resin. The mold shown in FIG. 6 is an example in which a cull insert 60 is movably provided in the mold opening / closing direction, and is supported by a resilient spring 61 so that an end surface protrudes from a parting surface. In this mold, when the underfill resin tablet 80 is supplied to the pot 42 and clamped, the cull insert 60 is pushed up against the elastic force of the elastic spring 61 (the state shown in FIG. 6), and the resin The tablet 80 is melted and the spring 61 is resilient.
The cull insert 60 is pushed down by the resilience of, and the filling of the resin into the underfill portion is completed. The molding pressure at the time of resin sealing depends on the urging force of the resilient spring 61, but the plunger 44 provided on the lower mold has a function of adjusting the amount of resin and a function of adjusting the pressure. The spring of the resilient spring 61 may be about 5 kg, and the plunger pressure of the plunger 44 may be about 30 kg. If it is set to such a degree, the resin tablet can be injected while being melted.

In order to inject the resin more quickly, for example, after the resin tablet 80 is clamped by the cull insert 60 and the plunger 44, the plunger 4
4, the molten resin is sent out, the movement of the plunger 44 is stopped immediately before the underfill portion is filled with the resin, and the underfill portion is filled by the urging force of the cul insert 60 in that state. This method has the advantage that surging can be prevented and the flash can be reduced.

When the cull insert 60 is depressed, the sealing resin 14 is set to be extruded just to the gate end, and the underfill portion and the side sealing portions 63a, 63b, 63c, 63d are sealed. When the resin 14 is filled, the plunger 44 is operated in a pulsed manner as described above, so that the sealing resin 14 can be sealed with a pulsation. This resin sealing method is equivalent to a method of performing resin sealing by controlling the speed of the plunger 44.

In each of the above embodiments, the semiconductor chip 12 is on the upper mold side and the substrate 10 is on the lower mold side. However, the semiconductor chip 12 does not necessarily have to be on the upper mold side. It is also possible to perform resin sealing with 12 as the lower mold side. In the above embodiment, the pot 42 is disposed on the lower mold 28, but the pot 42 is
6 can be adopted.

[0057]

According to the resin sealing method and the resin sealing apparatus for a semiconductor device according to the present invention, the periphery of the underfill portion of the molded article is closed by the release film, and the underfill portion is sealed by the transfer molding method. The sealing resin is filled with the sealing resin without causing unfilled resin or generating voids. can do. In addition, since the resin is encapsulated by the transfer molding method, reliable resin encapsulation is possible even for products with an extremely small underfill area or when encapsulating the resin using a sealing resin containing filler. As a result, highly reliable resin sealing can be performed without variation in quality, and efficient resin sealing can be performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a mold of a resin sealing device.

FIG. 2 is an explanatory diagram showing a state in which a resin is filled in an underfill portion.

FIG. 3 is an explanatory view showing a configuration of a mold for closing a periphery of an underfill portion.

FIG. 4 is an explanatory view showing another configuration of a mold for closing a periphery of an underfill portion.

FIG. 5 is a graph showing an operation of a plunger for controlling resin filling.

FIG. 6 is an explanatory view showing a method of providing a side sealing portion and performing resin sealing.

FIG. 7 is an explanatory view of an upper mold provided with side blocks as viewed from a parting surface side.

FIG. 8 is a cross-sectional view of a supporting structure of a side block in a mold as viewed from a gate side.

FIG. 9 is an explanatory diagram showing a method of underfilling using a side block.

FIG. 10 is a cross-sectional view illustrating a configuration of a semiconductor device sealed with an underfill.

FIG. 11 is an explanatory view showing a conventional method of filling a sealing resin into a gap between a semiconductor chip and a substrate.

FIG. 12 is a cross-sectional view illustrating another configuration of the semiconductor device sealed by underfill.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Substrate 12 Semiconductor chip 14 Resin for sealing 16 Bump 20 Release film 26 Upper mold 28 Lower mold 28a Lower block 40 Molded article 42 Pot 44 Plunger 50 Die runner 60 Cal insert 61 Resilient spring 62 Cavity insert 62a Cavity recess 62b Cavity insert 63a, 63b, 63c, 63d Side sealing part 66 Air flow path 68 Ultrasonic vibration part 70 Gate 80 Resin tablet 90 Elastic body 92 Air flow path 94 Metal pressing part 100a, 100b Side block

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fumio Miyajima 90, Kamikatoma, Tokura-cho, Hanishina-gun, Nagano Prefecture, Japan Apic Yamada Co., Ltd. (56) References 334106 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/56

Claims (9)

(57) [Claims] 1. A resin sealing method for a semiconductor device in which a sealing resin is pressure-fed to an underfill portion of a molded article having a semiconductor chip mounted on a substrate to seal a joint between the semiconductor chip and the substrate. When the molded article is clamped by a mold, the periphery of the underfill portion is closed by a release film except for a portion connected to a gate leading to the underfill portion, and the periphery of the underfill portion is released by the release film. A resin sealing method for a semiconductor device, wherein a sealing resin is pressure-fed to the underfill portion in a closed state to seal the bonding portion. 2. The method according to claim 1, wherein when the underfill portion is closed by the release film, a release film is pressed against a side surface of the semiconductor chip to fill only the inside of the underfill portion with the sealing resin. The resin sealing method for a semiconductor device according to claim 1. 3. The semiconductor device according to claim 3, wherein the release film is pressed against a side surface of the semiconductor chip via an elastic body which is elastically deformed by a clamping force for clamping a molded product when the underfill portion is closed by a release film. The resin sealing method for a semiconductor device according to claim 1. 4. When the underfill portion is closed by the release film, the sealing resin is applied to a side surface sealing portion provided between a side surface of the semiconductor chip and the release film and the underfill portion. The method according to claim 1, wherein the resin is filled. 5. When filling the underfill portion with the sealing resin, two side surfaces except for one side surface and the other side surface parallel to the one side of the semiconductor chip connected to the gate are closed. 5. The method according to claim 4, wherein the semiconductor device is sealed with a resin. 6. The method according to claim 1, wherein when the underfill portion is filled with the sealing resin, the sealing resin is filled by pulsating the resin. The resin sealing method for a semiconductor device according to the above. 7. A molded article having a semiconductor chip mounted on a substrate is clamped by an upper mold and a lower mold, and an underfill portion of the molded article is pressure-fed and filled with a sealing resin to form the molded article. A resin sealing device for a semiconductor device for sealing a joint portion with a substrate, wherein the semiconductor chip is housed in one of the upper mold and the lower mold,
A resin sealing device provided with a cavity recess for closing a back surface and a side surface of the semiconductor chip via a release film except for an end of a gate which communicates with the underfill portion. 8. An elastic body which is elastically deformed by a clamping force when clamping a molded product and presses the release film against a side surface of the semiconductor chip is provided on a side surface of the cavity concave portion. Item 8. The resin sealing device according to Item 7. 9. The resin sealing device according to claim 7, further comprising pulsating means for pulsating the sealing resin when the sealing resin is pressure-fed to the underfill portion.